1. Statement of the Technical Field
The present invention relates to nutritional compositions, and more particularly to nutritional compositions that are derived from colostrum of animals.
2. Description of the Related Art
Since the early 1970's whey proteins have been concentrated for uses in healthcare and for use in nutritional and functional foods, for example as an ingredient. These proteins include beta-lactoglobulin and alpha-lactalbumin, which are commonly extracted from bovine milk. More recently, lactoferrin and immunoglobulins also have been extracted from bovine milk, but to a lesser extent. Although the concentrations of lactoferrin (100-200 mg/liter) and the immunoglobulins (5-6% of total whey proteins) are low in milk, the concentrations of lactoferrin (1-2 g/liter), proline-rich polypeptides and immunoglobulins (70-80% of total whey proteins) are much higher in colostrum.
Some protein functions involve the binding of other molecules called ligands. Ligands can be drugs, hormones or antigens that can bind with proteins. Those compounds that can act as ligands but which normally are found naturally in animal bodies fall into three general classes: neurotransmitters, steroids (including the sex hormones), and peptides. The first two classes are considered to be bioactive, whereas peptides are not. (Bioactive is a phrase that describes a set of compounds which have an effect on animal cells that is in direct proportion to their number and which are produced either outside the body of the animal or only in specialized organs or systems thereof.) Peptides typically have a relatively low molecular weight and are the product of the sequential covalent bonding of several amino acids. For example, peptides typically are formed from about 4 to 100 sequentially bonded amino acids.
Proline-rich-peptides and/or non-ionic peptides are important in various biochemical processes. These peptides may be termed receptor peptides and are in fact very specialized types of proteins. They are believed to reside in or on the exterior surfaces of all animal cells (regardless of particular cellular function). When activated through interaction with a ligand, a receptor then transmits a biochemical message into the interior of the cell.
Peptides, such as proline-rich-peptides and non-ionic peptides, which function as ligands are produced in the ribosomes of all or very nearly all of the cells of animals and man. They are sometimes referred to as informational peptides because they often provide little or no nutritional value, but contain specific information to help trigger specific biological processes. The informational peptides also may help protect cells by re-orientating receptor sites often used by synthetic viral protein ligands. Thus, these peptides may help inhibit viruses from attaching themselves to those specific individual target cells by regulating immuno-modular and cytokine intercellular function and intracellular function.
Peptides generally are relatively small, at least in relation to most proteins which tend to have molecular weights of at least 20,000 Daltons. In general, peptides have a molecular weight of no more than about 1000 Daltons, although some might be larger, even perhaps as large as about 6000 Daltons. Nevertheless, they are significantly smaller than most proteins.
When a peptide leaves the cell in which it was produced, it moves throughout the body by way of the interstitial fluids between the cells and the circulatory system. In the blood and interstitial fluids, peptides tend not to agglomerate with themselves (i.e., they remain separate). This separateness allows the peptides to remain in forms in which they can bind with appropriate receptors. For instance, a peptide produced by one cell can be transported to and interact with the cellular function of a distant cell. When such an interaction occurs, a type of biochemical transmission to the cell interior is set into motion and this, in turn, induces some type of a response within the cell. One such cellular action is believed to be the production of additional peptides of the type bound to the cellular receptor.
As mentioned previously, some viruses take up residence in animal bodies by entering cells through particular types of receptors. If the necessary type of receptor already is bound to another ligand, such as a peptide, or the shape of the receptor does not or is no longer compatible with the viral ligand, then the virus cannot enter that given cell and must find another cell in which to enter. If all cells have the target receptor bound with other ligands, or there has been a conformational change of shape at the receptor site because of biochemical processes from within the cell, the virus' entry path is blocked and infection is averted.
When an animal, including a human, is healthy, it has a full (or very nearly full) complement of peptides. However, due to any one or more of a variety of factors, such as increased age of the animal, bodily abuse by environment or substance abuse, nutrition, suppressed immune system, and/or illnesses and diseases, an animal may fail to produce or maintain one or more of these types of peptides. Such failures often can be the first cause of illness. Return to health can be relatively quick and easy, however, when the missing peptide(s) is reintroduced into the body because such peptides can, as described above, “instruct” cells to create more copies of the peptides. These are commonly called “proline-rich-polypeptides” (PRPs), “cytokine precursors” or “immuno-modulating peptides”. Commonly, these peptides have been called the “software of the cell” or “software of the human operating system”, which refer to the information required for all living mammalian cells to function. The initialization of correct cellular function is started when a female lactating mammal first delivers the “colostrum” to a newborn mammal baby, which commonly is called “passive immunity”. In addition to such immunity, the colostrum also provides cytokine precursors to initiate many biochemical processes in mammalian cells. Thus, reintroduction of a small amount—perhaps a single copy—of one or more missing peptides to any infant, teenage, adult or elderly human, or any aged mammal, can quickly return cells in the body to their normal amount of the peptide(s) in question.
The target peptides can be derived from blood or from other mammalian bodily fluids derived from or in contact with blood. Such fluids include, but are not limited to, milk, colostrum, semen, urine, vaginal fluid, and the like. However, in materials such as milk and colostrum, for example, peptides are in what is essentially an impaired state because they are agglomerated with or on much larger biochemical macromolecules i.e. fats or other proteins. Additionally, ingestion by eating or drinking certainly denatures the peptides because of the acidic conditions of the stomach and the relatively aggressive enzymatic action of the digestive tract. Thus, although many external sources of peptide ligands are available, these peptides often are in a form that renders them useless for the desired effect. Accordingly, processing or refinement of such external sources is necessary.
Of the external sources of peptides, the one that seems to provide them in the highest concentrations and is most widely available is colostrum. This material has been the subject of numerous processing methodologies. However, almost all of the previously described processing methods appear to have been directed at collecting or isolating biologically active macromolecules that are much larger than peptides, such as, for example, proteins, lactoferrin, immunoglobulin, lipids, etc.
Importantly, present colostrum processing methods tend to encourage relatively high fluid pressures and much lower yields of peptides as a side effect of fast processing speeds and current technologies used. For those references dealing with ways to isolate large molecules such as immunoglobulin, lactoferrin, etc., this is not surprising because such macromolecules are relatively hearty and capable of withstanding such pressures. Peptides, however, respond quite differently to high processing pressures. In particular, many types of peptides can be denatured at pressures ranging from about 210 kPa (approximately 30 psi) to about 690 kPa (approximately 100 psi). For example, peptides involved in the prevention of viral infections are among those that can be denatured at the lower end of this range of pressures (less than 10 psi). The term “Denatured”, with respect to a peptide, connotes an alteration or conformation change from the natural state due to, for example, physical forces (e.g., adhesion to another molecule(s), exposure to excessive temperature or pressure during processing, etc.), chemical reaction (e.g., scission due to exposure to excessively acidic or basic conditions), enzymatic, degradation, and the like.
Accordingly, there remains a need for a method of processing animal-derived fluids that result in an end product which is peptide-rich, with the same efficacy as in its native state, but substantially free from other materials that can denature such peptides, and thus able to fully express their peptide bioactivity without steric hindrance, and increase liquid diffusion of these peptides.